title: Photolabile, spacer-modified oligosaccharides for probing malto-oligosaccharide binding sites in proteins.
abstract: O-Deacylation and S-deacylation of the diastereomers of 2-azido-4-S-benzoyl-4-mercaptobutyl 2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranoside (9) with methanolic sodium methoxide and coupling of the resulting thiol to methyl 3,4-anhydro-6-deoxy-beta-L-arabino-hex-5-enopyranoside (2) gave the corresponding diastereomers of the spacer-modified disaccharide methyl 4-S-(3-azido-4-alpha-D-glucopyranosyloxybutyl)-6-deoxy-4-thio-alph a-D-xylo-hex-5-enopyranoside (10). Glucosylation of the diastereomers of 10 with alpha-cyclo-dextrin-CGTase and treatment of the products with beta-amylase gave the diastereomers of the spacer-modified oligosaccharides methyl 4-S-(3-azido-4-alpha-maltosyloxybutyl)-6-deoxy-4-thio-alpha-D-xylo -hex-5-enopyranosides (11) and 4-S-(3-azido-4-alpha-maltotriosyloxybutyl)-6-deoxy-4-thio-alpha-D- hex-5-enopyranosides (12). The diastereomers of 10 each had a good affinity for pancreatic alpha-amylase and the maltose-binding protein from E. coli. The affinities of the diastereomers of 11 and 12 were higher by at least one order of magnitude.
authors.affiliation: Institut für Organische Chemie und Biochemie, Universität Freiburg, F.R.G.
authors.forename: J
authors.initials: J
authors.lastname: Lehmann
authors.forename: L
authors.initials: L
authors.lastname: Ziser
mesh_terms: D018528:ATP-Binding Cassette Transporters; D001665:Binding Sites; D002240:Carbohydrate Sequence; D002352:Carrier Proteins / Q000378:metabolism; D029968:Escherichia coli Proteins; D007700:Kinetics; D058619:Maltose-Binding Proteins; D015335:Molecular Probes / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data; D009004:Monosaccharide Transport Proteins; D009844:Oligosaccharides / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism; D010777:Photochemistry; D011506:Proteins / Q000378:metabolism*; D000516:alpha-Amylases / Q000378:metabolism
chemical_list: D018528:ATP-Binding Cassette Transporters; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D058619:Maltose-Binding Proteins; D015335:Molecular Probes; D009004:Monosaccharide Transport Proteins; D009844:Oligosaccharides; D011506:Proteins; C461599:maltose transport system, E coli; D000516:alpha-Amylases